Primary canine hypoplasia is a lesion located on the mesial aspect of the facial surface on the cervical half of the primary canine tooth. It appears as a roughly circular or oblong, white or brown opaque area 1-5 mm in diameter with a flat or concave presentation. The literature on primary canine hypoplasia is very limited. The studies reported have not had adequate or appropriate samples to provide confidence on the scope of primary canine hypoplasia. In addition, a higher level of confidence in the scope of this problem needs to be attained and the practicing dentist needs to be aware of the problem. This research is intended to satisfy the needs resulting from the lack of awareness existing at the present time. The specific aims of the study described in this protocol are to determine the prevalence of primary canine hypoplasia among Mississippi children, to determine the association of the lesion with race, rural/urban locations, fluoridated drinking waters, and dental caries. In addition, the data will be analyzed to determine whether preventive modalities should be developed and advocated. The study population will consist of four- and eight-year- old children enrolled in accredited private, and public pre-schools and elementary schools in Mississippi. Sample sizes of 660 children will be randomly selected in each of the four groups determined by two age groups and two race groups (black and white). The resultant contingency tables will be analyzed by employing the Grizzle, Starmer, and Koch methodology via the CATMOD procedure on SAS. A hypoplasia index will be used to score the absence or presence (and the degree) of the lesion. The caries index (def) will be used to record the condition of each tooth. Examiners will be standardized in the use of both indexes. Fluoridation histories will be obtained for each child by having parents complete a brief questionnaire.